Pre-strop Sharpness?

Tue Sep 25, 2012 10:05 am

So as I continue to refine my skill, I'm finding that the shavability of my knives pre-strop is often nonexistent to barely there. But after a mere dozen or so strokes on some loaded strops, hairs are popping with ease. Now, obviously I get that strops clean up the edge dramatically and that's why we use them, to obtain these kind of results. I'm just wondering what's possible from stones only, and if I should hold myself accountable for a solidly shaving edge from stones only? I want to be as good as I can be, and so I'm wondering if the pros and veterans here obtain easy shaving edges before going to a strop? Is this a realistic goal?

Re: Pre-strop Sharpness?

Tue Sep 25, 2012 10:51 am

A strop should be used to enhance a very sharp edge. If you cannot shave by the finish of your last stone then your burr formation is likely way too big. The green brick (which I use often) is capable of very high degree of sharpness that will effortlessly remove hair well before stropping.

From your description I would suspect that not enough work is being done on each stone and the burr is not properly being reduced as you finish with each stone. Under a microscope you would likely find a burr or fin of metal that has been polished by stropping but not removed.

Re: Pre-strop Sharpness?

Tue Sep 25, 2012 11:11 am

Agreed. I set a new bar for myself when I was learning to sharpen--I thought I had gotten pretty good at it, but then read on a straight razor forum that you shouldn't go past 1k if the edge won't shave(roughly, but it should shave). Spend more time on the stones, and don't rush--consistency is key.

Re: Pre-strop Sharpness?

Tue Sep 25, 2012 12:02 pm

Indeed, this is the type of feedback that makes this forum so valuable. If one pays attention, they can significantly reduce the learning curve, while at the same time learn something new every time they lay their edge on the stone. Excellent stuff gentlemen, as usual.

Re: Pre-strop Sharpness?

Awesome. Thanks for the quick replies. I had heard somewhere along the line that if you can't shave after 1k, you should do more work, but it's nice to have that confirmed by authoritative sources.

I usually do something like alternating sides with 11 strokes, then 10, 9, 7, 5, 4, 3, 2, 1 and then do edge trailing 'strop' strokes with decreasing pressure and then debur with cork between stones. With that said, do we think my problem is more due to a lack of time per stone or a technique deficiency?

Re: Pre-strop Sharpness?

Tue Sep 25, 2012 12:51 pm

I don't count strokes, but that sounds like a lot, especially if you are using decent pressure at the start. 21 strokes with goodly pressure will make a notable dent in removing prior scratches on the stones you have. Except maybe the Norton, I only have 1 Norton stone.

*edit*I just asked about deburring, then realized you just said you deburr with cork between stones.

I would guess it might be just a time issue. If you get a consistently finished edge after stropping, it's just not shaving-sharp before stropping, its gotta be that. Does sound like you are spending a good amount of time on them though.

Re: Pre-strop Sharpness?

I don't count strokes I watch the bevel, typically its a better indicator to progress.

The number of strokes needed has too many factors, its simply something you cannot put a number to.

I would stop de-burring after each stone. Cutting into a object will cause the burr to fracture and damage the apex of the edge. To add, cutting a object will damage a fresh edge so IMO de-burring by dragging the edge through a object is counterproductive to the action of sharpening.

Try to use decreasing pressure as you work with a stone until the last few trailing strokes are feather light. This typically helps reduce the size of the burr or completely remove it.

Re: Pre-strop Sharpness?

Wed Sep 26, 2012 12:47 am

Get rid of the burr as much as you can. As Eamon says, in the shaving community we won't go to a higher grit unless the edge shaves. That being said, it's much easier to do that with a razor than with a knife because you don't tend to build a burr on a razor in the first place.

My 1k edges need to shave and have to be able to push cut paper before I move on.